The role of gastrointestinal pathogens in inflammatory bowel disease: a systematic review

• Main Authors: Jordan E. Axelrad, Ken H. Cadwell, Jean-Frederic Colombel, Shailja C. Shah
• Format: Article
• Language: English
• Published: SAGE Publishing 2021-03-01
• Series: Therapeutic Advances in Gastroenterology
• Online Access: https://doi.org/10.1177/17562848211004493

The inflammatory bowel diseases (IBD), comprising Crohn’s disease (CD) and ulcerative colitis (UC), are chronic, progressive, inflammatory conditions of the gastrointestinal tract. Imbalance in the gut microbial community, or dysbiosis, and the subsequent immune response, represent the critical relationship between genetic susceptibility, microbes, and environment factors, that result in IBD. Gastrointestinal pathogens – a common cause of dysbiosis – have been implicated as an environmental trigger in new onset IBD, as well as flare of existing IBD. In this article, we systematically review clinical data regarding the association between specific gastrointestinal pathogens and IBD. Numerous bacteria, viruses, fungi, and parasites have been implicated in the pathogenesis of IBD, and exacerbations of existing disease. In this article, we will also specifically discuss the less recognized microbes that have an inverse association with IBD, including certain bacterial pathogens, such as Helicobacter pylori , and parasites, such as Trichuris species. Future prospective and experimental studies are required to establish causality and clarify potential mechanisms of enteric pathogens in modifying the risk and course of IBD.